Multi-methodological three-dimensional investigation of open- and closed-system Pingos in northwestern Canada (Pingo3D)

加拿大西北部开放和封闭系统 Pingos 的多方法三维调查 (Pingo3D)

• 批准号: 515411322
• 负责人: Professor Dr. Christof Kneisel
• 金额: --
• 依托单位: Arbeitsbereich Physische Geographie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/515411322?language=en
• 关键词: Multi; methodological; three; dimensional; investigation

Pingos are one of the most important landforms in the Arctic and are key features of polar permafrost landscapes. They are sensitive to changing climatic and hydrological conditions, which is why their spatial distribution is likely to change significantly in the course of current global warming. This is due to higher temperatures but also to changing permafrost hydrology, which plays an essential role during formation, but also during decay of pingos. The project aims to gain new insights into the internal structure of open- and closed-system pingos and their genesis by using a combined approach of three-dimensional geophysical measurements and various in-situ data. Possible interactions between surface and subsurface properties are the main focus. Geoelectrics, induced polarisation, georadar and potentially electromagnetic will be used to perform the three-dimensional geophysical investigations, as they allow a high-resolution characterization of the near-surface subsurface as well as a good delineation between frozen and unfrozen areas. In addition, surface temperature loggers and several boreholes will be used to investigate the spatiotemporal variability of the thermal regime. Surface parameters include various topographic features such as vegetation type and height. These surface parameters will be determined using high-resolution, drone-based terrain models and orthophotos and examined for changes over the course of the project. Long-term changes will be additionally captured by a time series analysis of Landsat data as well as a deformation analysis based on an InSAR evaluation. Local surface hydrology and hydrology within the active layer will also be investigated and modelled as another link between surface and subsurface hydrology. The combined approach of three-dimensional geophysics, remote sensing methods, hydrological modelling and various in situ datasets will allow detailed investigation of the internal structures of pingos while exploring the complex interactions between surface and subsurface processes. The synthesis includes the identification of variables influencing surface and subsurface conditions and any interactions between surface and subsurface parameters. The holistic approach will enable the development of improved conceptual 3D models of pingo genesis to explain the cryo-hydrogeologic processes that occur in Arctic geosystems. These processes are elemental to the life cycle of pingos, but are also important in other Arctic permafrost landscapes. Based on these findings, site-specific scenarios for future permafrost dynamics and their impacts on landforms can be developed. In addition, based on the expected results of the combined methodological approach, the broader scientific significance of the study lies in the ability to establish best-practices for investigating zones of unfrozen ground in permafrost regions and to better understand the complex permafrost hydrology.

平戈斯是北极最重要的地貌之一，也是极地永久冻土景观的主要特征。它们对气候和水文条件的变化很敏感，这就是为什么在当前全球变暖的过程中，它们的空间分布可能会发生重大变化。这是由于更高的温度，但也是由于变化的永久冻土水文，这在形成过程中起着至关重要的作用，但也在平果的腐烂过程中发挥着重要作用。该项目旨在利用三维地球物理测量和各种现场数据相结合的方法，对开放和闭合系统平果的内部结构及其成因有新的见解。表面和次表面性质之间可能的相互作用是主要焦点。将使用地电学、感应极化、地质雷达和潜在的电磁手段进行三维地球物理调查，因为它们能够高分辨率地描述近地表的特征，并能够很好地划定冻结和未冻结地区之间的界限。此外，还将使用地面温度记录仪和几个钻孔来研究热状况的时空变异性。地表参数包括各种地形特征，如植被类型和高度。这些表面参数将使用高分辨率、基于无人机的地形模型和正射影像来确定，并检查项目过程中的变化。此外，还将通过对陆地卫星数据的时间序列分析以及基于InSAR评估的形变分析来捕捉长期变化。还将对活跃层内的当地地表水文学和水文学进行调查，并将其模拟为地表和地下水文学之间的另一种联系。三维地球物理、遥感方法、水文建模和各种现场数据集相结合的方法将使我们能够详细调查平戈斯的内部结构，同时探索地表和地下过程之间的复杂相互作用。综合包括识别影响地表和地下条件的变量，以及地表和地下参数之间的任何相互作用。整体方法将使改进的Pingo成因概念三维模型的开发成为可能，以解释北极地质系统中发生的低温水文地质过程。这些过程是平戈斯生命周期的基本要素，但在北极其他永久冻土地貌中也很重要。基于这些发现，可以为未来的永久冻土动态及其对地貌的影响制定特定地点的情景。此外，基于综合方法学的预期结果，这项研究的更广泛的科学意义在于能够建立调查多年冻土区未冻土区的最佳做法，并更好地了解复杂的多年冻土水文学。